The boundaries of the sequential plan are drawn to demonstrate an absolute difference of 5% in 28-day mortality rate between the two treatment arms, assuming a 20% mortality rate in the crystalloids group, and with alpha and beta of 5% and 10% respectively. The analyses will be performed every 100 deaths. The figure displays the boundaries of the sequential plan. Briefly, Z represents the difference between the two groups and V the number of patients that have been included. When a boundary is crossed, the enrollments in the study must be stopped, and the conclusion depends on which boundary has been crossed (see figure). Simulations allow to estimate how many inclusions are saved: when difference in mortality rates is nil, 1109 patients have to be included to reach the conclusion. When difference is 5%, 1477 patients have to be included to reach the conclusion.